Panel spacer



FIG. 1 is a front, top perspective view of a panel spacer embodying my design;

FIG. 2 is a top plan view of the panel spacer as shown in FIG. 1; and,

FIG. 3 is a front end view of the panel spacer as shown in FIG. 1; 

The ornamental design for a panel spacer, as shown and described. 